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Unlikely base MEC using “upgraded LT1”

 
Old 12-26-2018, 08:06 PM
  #81  
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Thanks JerriVette; not saying many of us would not go to a Jegs or similar, just actually sharing here a seen Chevrolet dealership service department invoice, with its pricing, for a C7 total replacement motor.

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Old 12-26-2018, 08:11 PM
  #82  
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Originally Posted by stepheng View Post
Would there be any HP benefit from using the port and direct injection system (from the new ZR1) on the LT1?
Clean valves. No need to pull the engine out to blast it in order to clean the DI deposits.

Easy to mod for whatever power you want in the aftermarket by simply upgrading the port injection. Caveat, the ECM might be locked forever.

Originally Posted by elegant View Post
The upcoming ME will have, year one and probably after that , a LT1 derived, but enhanced motor. The LT1 started to be designed about eight years ago, appeared in GM trucks six years ago, an eternity in terms of motor developments. The LT2 (for lack of a better code) will be an LT1 with major developments such as the four major ones debuted in the brand new 4 cyclinder GM truck motor, though some of the components of that motor will not be in the LT2, e.g., the turbo.

Thanks to JerriVette for finding this video:

https://youtu.be/9w3HItRrbI4

Here then are some of those potential C8 motor enhancements coming from that new GM truck motor.

1) Electric water pump, with varying amounts of flow based on need, not related strictly to RPM;
2) Advance engine heat management — both for quicker, better fuel and emissions measures on start up, but also for long term motor longevity and power capabilities;
3) Sliding or “axial” camshaft, giving the best variability for both power and economy, not being, as most previous engines are a compromise camshaft needing to balance the two competing needs. Also near infinite adjustability of valve lift.
4) Transitioning from previous two stage/two step oil pumps to a continuously variable output one — for better engine efficiency.

With these enhancement we can easily see the ME’s LT2 approaching or exceeding 500 HP, and a roughly similar amount of torque.


Thanks! This info is gold. I'm surprised no one is discussing the axial cam. Infinitely adjustable valve lift is actually a killer tech in DOHC, let alone in OHV. This is enough to propel OHV forward and might even topple DOHC. Has anyone noticed the Caddy V8 doesn't even have variable lift? Not even discrete!

Okay, it's a discrete variable lift on intake valves, and then it's also used to shut off the intake and exhaust valves for AFM. It's solenoid operated so probably limited in terms of RPM, but pushrods can't rev much anyway. Think of the cam in cam from the Viper that took it from 500hp to 600hp. You can get that in the C8 now.

I'll take variable phase and lift OHV 6.2L over a 5.5 turbo DOHC that only has variable phase anyday.
https://jalopnik.com/heres-a-close-u...our-1830571473

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Old 12-27-2018, 02:26 AM
  #83  
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Originally Posted by Foosh View Post
Sales and performance matter more than perception. Keeping Corvette a budget performer has been the key to its continuing success. You just can't sell many $100K 2-seat sports cars, certainly not more than 10-15K annually, worldwide.
FWIW, Ferrari sold 8,400 cars during 2017 (last known year of sales).
They artificially keep production low.
God knows how many they would sell if they tried to meet demand.
GM has been incredibly successful w/ a "halo" car starting at around $60K, .
I think price/value is probably the real key to its success...that, plus the sexy exterior design it has always had.

Originally Posted by elegant View Post
Much cheaper for an OHV motor to be repaired/replaced. I believe I remember somewhere that a Chevy OHV V8 averages 800 fewer parts than a 32V, DOHC TT motor.

BTW, we have seen a C7 invoice that showed $17,000 for a completely new LT1 (including removing of the lunch one, install of the new one). And in comparison an LT4 replacement with a new one is $30K.

Wonder what a C8 Z06 TT, DOHC, 32V motor would cost if a new one were needed? For sure however, less than an exotic’s comparable motor by far.
When going to buy a new car, who worries about replacing the odd blown motor?
That's why warranties exist.

IF someone here is thinking of buying a C8 AND driving it hard after the warranty expires, they are damaging their liver with too many adult beverages.
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Old 12-27-2018, 06:49 AM
  #84  
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Originally Posted by JerriVette View Post
Just shooting the breeze..can anyone tell us the replacement cost for a mercedes amg gts engine?

great tech...but how much does it actually cost to replace one of these twin turbo hot V v8 from mercedes benz?

did a quick google and is this accurate for a 2000 mile used engine...? And if so how much is a new one from germany?

https://www.ebay.com/i/253354074254?...176000ffe3ad85

I kind of prefer the cost structure on the possible 520 hp lt1 derivative.
the vette has always been about affordable performance but dohc will be needed to meet ever tightening emissions standards and still meet HP goals

varying 4 cams is part of the need and while the pushrod motors have been developed to the zenith possible, there are some inherent advantages to a dohc configuration that cannot be overlooked.

weight, and pacakging and cost are the 3 issues that held back the lt5 c4 zr1 motor from being developed 1996 model year would have done 475 hp without much ado and 500 + is easy target

and yet the engineers can do the same with a pushrod motor to a point with good hot rodding and variable single cam and cyl deactivation

I don't think that stuff would hold up as well lapping at 175 plus though. the dohc engines shine there and durability hasn't been a problem it's back to cost weight and pakcaging

ford saw the light a while back and made the high hp dohc v8s almost as cheap and light as the pushrod motors look at the coyote crate engines.

volume manufacturing will get the price down, just like it would have with the old lt5 I'm sorry, but from an engineering standpoint, dohc turbos and electric will rule the future, like it or not
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Old 12-27-2018, 08:16 AM
  #85  
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AS an avid corvette enthusiast for decades i have to say i think gm s powerplants with ohv s are better than fords motors but dont be insulted ...(i stated upfront Im a corvette enthusiast)

im sure the future gm twin turbo dohc engine in the back half of the c8 will be world class top notch..,

if its my money.....that Im spending as the c8 releases....ill opt for the ohv approximate 520 hp v8 ...

i daily these cars and 520 hp for 70 odd grand...and im happy...

for the guys who want to wait a year or two for the dohc tt ..more power to them...

im turning sixty this year and I want to buy myself a present...

520 is cool..500 is cool....less than 490 and who knows...maybe the twin turbo dohc version will be the pick...

we dont know anything offiical yet...

but i love the truck derived lt and ls powerplants...

inexpensive and durable as hell and powerful..

20 years of various ls and now lt powerplants and all their attributes...

to each their own

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Old 12-27-2018, 10:21 AM
  #86  
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The way I see it is this. It seems the recent Camaro Zl1 1Le has supplanted the Corvette at its price point. I’m sorry, I have never been a big fan of the Camaro, but at 70k and a 7:16 Nurburgring run, it seems to have out corvetted the corvette. There,folks, is your pushrod, manual trans, cargo space “Great Performance Car For The Money” with a crappy interior. Now you can be free to build a true world beating sports car with no Qualifications and elevate both brands.


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Old 12-27-2018, 10:53 AM
  #87  
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Originally Posted by JerriVette View Post
AS an avid corvette enthusiast for decades i have to say i think gm s powerplants with ohv s are better than fords motors but dont be insulted ...(i stated upfront Im a corvette enthusiast)
There is no question GM has evolved the pushrod to amazing heights and they should be respected for that achievement, but it really is time for a change...particularly since they want to target Porsche, etc. buyers, regardless of the low probability of attracting very many.

im sure the future gm twin turbo dohc engine in the back half of the c8 will be world class top notch..,

if its my money.....that Im spending as the c8 releases....ill opt for the ohv approximate 520 hp v8 ...

i daily these cars and 520 hp for 70 odd grand...and im happy...

for the guys who want to wait a year or two for the dohc tt ..more power to them...

im turning sixty this year and I want to buy myself a present...

520 is cool..500 is cool....less than 490 and who knows...maybe the twin turbo dohc version will be the pick...

we dont know anything offiical yet...
If GM doesn't make the base car 500hp, it's a fail IMO.
500 is a good marketing number.


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Old 12-27-2018, 10:55 AM
  #88  
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Originally Posted by Dominic Sorresso View Post
No interest for a truck motor in an ME car.
Wasn't that the same formula Ford used for the original GT40?
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Old 12-27-2018, 01:30 PM
  #89  
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Originally Posted by JD_AMG View Post
Christmas facts:


Confirmation bias. Although any list I've ever seen always has GM's pushrod V6 on it. Any unbiased list of performance engines will have GMs SBC(gen1 and gen 3+) on it.



hp/l is completely and utterly useless on production cars, and is plain out ricer math. Displacement is basically meaningless in this context and peak HP doesn't tell the whole story. Pushrod engines are lighter even when displacements are not equal. The 6.2L LS3 is lighter and smaller than the 5L Coyote by a good margin:


And before you start trying to quote weights, keep in mind that GM likes to weigh their engines with the 60lbs clutch assembly attached. The LSx family is under 400lbs undressed... That is in the range of smaller displaced aluminum DOHC V6s that make a fraction of the power and are still physically bigger...

Heres another good size example, how about a big ole 6.2L next to a 1.8L I4?


Whoops looks like the pushrod engine is comparable in size while making over double the power and torque.


You mean like the 488...oh whoops
But in all seriousness, look at the cost of those NA engines spinning to the moon to make power. Yea I think Ill take the significantly cheaper/smaller/lighter pushrod V8 that only needs to rev to ~6500rpms to make power and doesn't need a rebuild every 20K miles.



Yea its a CarAndDriver interview where when asked about DOHC engines Winegarden says and I quote: " GM's party line is that some customers want what it calls "high-feature engines." " - in other words BS marketing hype.
https://www.caranddriver.com/feature...-gets-its-due/
More like $700 cost to manufacture. I'm, a suspension guy, so roll couples to me are very important. The geometry compromise required for high CGs forces me to go OHV. My 08 Z is the greatest Vette yet because of the best LS engine yet, the magical 7000 rpm LS7. Outside suppliers caused the head and valve fail problems.


Other Lemans teams complained to the FIA of the advantages of OHV engines and consequently, Corvettes were penalized severely since the C5R. I have C5R square ported heads, timing chain and a cam that gives me reliable 590HP at the rear.
It took from 98 'till 2001 to make the the LS engine decent. The LS6 was the beginning of the super Chevy engine. The C4 GS could beat the C5 right up until the 02 Z. Factory claimed 330 hp, but none ever dynoed < 370Hp.
It out handled the C4 505 hp ZR1 and was a much better car. I owned a 93 ZR1 which I took to Europe. That magic LT4 actually weighed less than the first LS1 by 40lbs. Both coupled to the Tremec T56. The early LS1s turned out to be real disasters. Here is my roadster with a LT4 and LS1. The LS1 is heavier, that's without including the much larger radiator, the two extra gallons of coolant and a huge oil cooler and plumbing. Still would't run cool. Internal design flaws were the culprit. GM revised water jacketing and oil passages and water pump flow.
The C4 LT4 gained 20 hp by it's reverse cooled gear driven water pump system. It took up far less space than the LS1. Much design revision was required including moving the engine forward 3 inches to clear the firewall. Both engines had 420 HP but the LS1 car ended up 220 lbs more because of all the mods required to install the engine.


. If you want real HP, you must start with iron block truck LS engines. There are no DOHC engines that can come close in anyway. If you want a decent Euro car, put a LS7 in it.
http://www.superchevy.com/how-to/090...ngine-history/
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Old 12-27-2018, 03:34 PM
  #90  
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http://www.mercuryracing.com/mercury...-crate-engine/
You mean an ls7 like this one. I’m all in
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Old 12-27-2018, 04:27 PM
  #91  
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On second look, that new 2.7L Silverado engine has integrated exhaust manifolds to meet new emissions standards. That will clobber power substantially. Whatever is gained from new variable valve timing and all the other bits is lost easily with the single port exhaust. Lotus neutered engines with this design starting from about 10 years ago, and looks like Chevy is ready to follow. Shame.

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Old 12-27-2018, 07:01 PM
  #92  
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Originally Posted by SBC_and_a_stick View Post
On second look, that new 2.7L Silverado engine has integrated exhaust manifolds to meet new emissions standards. That will clobber power substantially. Whatever is gained from new variable valve timing and all the other bits is lost easily with the single port exhaust. Lotus neutered engines with this design starting from about 10 years ago, and looks like Chevy is ready to follow. Shame.
that is done to minimize turbo lag. Turbo lag is a terrible thing to experience. Even BMW who prides themselves with a “drivers car” has major lag in their turbo motors.
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Old 12-27-2018, 07:03 PM
  #93  
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Originally Posted by NY09C6 View Post


that is done to minimize turbo lag. Turbo lag is a terrible thing to experience. Even BMW who prides themselves with a “drivers car” has major lag in their turbo motors.
It has that benefit for turbo. However, it's used on engines without turbo as well to heat up the catalyst and engine faster. My understanding is that it actually places a heavier burden on the cooling system as the water jackets pick up more of the exhaust heat, though it may serve to keep the catalytic converter alive longer in hi po applications.
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Old 12-27-2018, 07:06 PM
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Well I suppose spending more for the same or less performance has always been a thing for Porsche owners. Your idea of GM doing this just might work to attract them. On the other hand, until GM starts stocking their service waiting area with free $5 lattes they probably won’t jump ship.

QUOTE=sunsalem;1598570758]There is no question GM has evolved the pushrod to amazing heights and they should be respected for that achievement, but it really is time for a change...particularly since they want to target Porsche, etc. buyers, regardless of the low probability of attracting very many.

If GM doesn't make the base car 500hp, it's a fail IMO.
500 is a good marketing number. [/QUOTE]
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Old 12-27-2018, 07:24 PM
  #95  
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Originally Posted by NY09C6 View Post


that is done to minimize turbo lag. Turbo lag is a terrible thing to experience. Even BMW who prides themselves with a “drivers car” has major lag in their turbo motors.
Turbo manufacturers need to look at the design F1 is using to reduce lag.

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Old 12-27-2018, 07:34 PM
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Originally Posted by sunsalem View Post
Turbo manufacturers need to look at the design F1 is using to reduce lag.
48v hybrid systems with electric turbo assist are the likely fix (audi will be first). But you are spending more money for more complexity for similar performance to a large ci motor. Sure you will save a few dollars at the pump but you give it back in other areas.
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Old 12-27-2018, 07:36 PM
  #97  
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Originally Posted by SBC_and_a_stick View Post
It has that benefit for turbo. However, it's used on engines without turbo as well to heat up the catalyst and engine faster. My understanding is that it actually places a heavier burden on the cooling system as the water jackets pick up more of the exhaust heat, though it may serve to keep the catalytic converter alive longer in hi po applications.
I cannot disagree, your point is relevant.

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Old 12-27-2018, 08:25 PM
  #98  
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I have heard the 48 volt syste, will be used to spin up the turbos for much less turbo lag
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Old 12-27-2018, 08:46 PM
  #99  
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Originally Posted by ConcernedCitizen View Post
The way I see it is this. It seems the recent Camaro Zl1 1Le has supplanted the Corvette at its price point. I’m sorry, I have never been a big fan of the Camaro, but at 70k and a 7:16 Nurburgring run, it seems to have out corvetted the corvette. There,folks, is your pushrod, manual trans, cargo space “Great Performance Car For The Money” with a crappy interior. Now you can be free to build a true world beating sports car with no Qualifications and elevate both brands.
Let me ask you, if the pushrod engine is so "bad" and not "world beating" then why do world beating supercars like the Ultima GTR use it, when they could use any other engine they wanted? Its not like that car is built with being cheap in mind, its built strictly for performance driving and lap times, yet it uses the "old tech" pushrod V8. Its almost like the engine has some kind of big advantage like weight and size...oh wait it does.
Why does Saleen use a pushrod engine in their S7 super car?
Why do so many one-off supercars use the LSx and not something like a Coyote instead?
Why does a big tuner like Steve Morris build high powered V8s based off LSx architecture (4000+hp)? Why even waste the time when he could strictly build OHC engines?
If DOHC V8s are so much better why are LSx's the most commonly swapped engine on the market, being swapped into S2000s, 240SXs, Skylines, Supras, WRXs, EVOs, Mustangs, Porsche's (911s and 944s), BMWs, Miatas, 350Zs, and just about any other car out there? Why are they replacing their "high tech" DOHC / turbo engine with some low tech pushrod V8, and why more often than not does the car become lighter, handle better, and always end up being faster? Its not cost, they could easily find a junkyard Mod motor, Northstar or Japanese V8 for pretty cheap. Ill give you a hint, those engines dont fit without major cutting, and they are heavy.

Why isn't it common (or even heard of) to swap DOHC V8s into Corvettes?

Again results are what matters, not bench racing about irrelevant details. If a car is running a low 7 minute Nring time and is put held together with popsickle sticks then clearly the engineers are onto something, despite what others are doing.

Ill take whatever engine gives better results, and thus far its been a pushrod V8.
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Old 12-27-2018, 08:53 PM
  #100  
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Originally Posted by Rkreigh View Post
ford saw the light a while back and made the high hp dohc v8s almost as cheap and light as the pushrod motors look at the coyote crate engines.

volume manufacturing will get the price down, just like it would have with the old lt5 I'm sorry, but from an engineering standpoint, dohc turbos and electric will rule the future, like it or not
While the Coyote is vastly better than the previous mod motors it still doesn't stack up to the LSx/LTx. Look a bit up at my previous post, you will see a picture of a Coyote next to an LS3, the Coyote is massive in comparison and heavier, while making less power, less torque and getting worse gas mileage.

If you were to take the LS3 and swap it into a same year Mustang not only would the mustang accelerate quicker, it would brake better and handle better as well - all due to a lighter engine that is more compact, allowing it to be mounted lower in the chassis and closer to the center of the car as well. To top it off the engine itself has a much lower center of gravity as well.

Now think about that for a second, what is so great about a DOHC engine again when we are talking about limited HP production cars? Why would you want something like a Coyote, as great as it is, when the LSx/LTx is that much better?
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